HS2 Launches First 170 Metres of Duddeston Junction Viaduct
The first section of HS2’s complex Duddeston Junction Viaduct has been launched over Birmingham’s live railway network, beginning the final crossing of six railway tracks on the approach to Curzon Street Station.
The first 170 metres of Duddeston Junction Viaduct are now in place on the Birmingham approach to Curzon Street Station, beginning the final viaduct crossing of the railway lines below. Engineers launched the first section over two freight lines on 19 August, starting work on a structure that will extend for roughly 700 metres.
The completed viaduct will cross six railway tracks and rise about 12 metres above them. Its alignment is curved rather than straight, and the first section follows a 3% gradient — details confirmed in the completed 170-metre phase of the curved structure reported the following day.
That geometry is being built into one of the least forgiving parts of the route: a live railway junction where construction cannot simply clear the ground and proceed uninterrupted. Seven spans have to be launched over the operational railway, while further sections will be craned into position. The result is a construction sequence shaped as much by the tracks beneath the viaduct as by the structure being assembled above them.
For High Speed 2, the Duddeston Junction Viaduct is a concentrated example of what building a new railway through an existing city actually involves. The route has to gain height, maintain its gradient, follow a curve and pass over freight and other railway lines without turning the junction into an empty construction site.
Launching the opening section over two freight lines is therefore more than a routine start to a 700-metre structure. It establishes the viaduct’s position and demonstrates the method needed for the spans that must cross the remaining live tracks, with cranes taking over where launching is not the chosen approach.
The first 170 metres do not complete Duddeston Junction Viaduct, but they begin its final railway crossing on the approach to Curzon Street Station. What follows is a sequence of launches and lifts that will carry the structure across all six tracks, leaving the railway below in place while the new line rises above it.